Norden bombsight

The state of the art of Allied-forces bombing in 1944 was based upon a mostly-visual targeting involving a complex sighting mechanism, and upon the American-devised method of assembling great battle formations that would overfly the target within minutes.

The mechanism used by the lead craft of a battle group over eastern Netherlands on 22 February 1944 was the Norden Bombsight, or "Stabilized Bombing Approach Equipment." This was a fantastically complex machine of more than 2000 parts that could account for elevation, flightspeed, windspeed, wind direction  and could, in conditions of good visibility, deliver ordnance with unprecedented accuracy.